add_cell Subroutine

    subroutine add_cell(me,val,int_fmt,real_fmt,trim_str)

    implicit none

    class(csv_file),intent(inout) :: me
    class(*),intent(in) :: val  !! the value to add
    character(len=*),intent(in),optional :: int_fmt  !! if `val` is an integer, use
                                                     !! this format string.
    character(len=*),intent(in),optional :: real_fmt !! if `val` is a real, use
                                                     !! this format string.
    logical,intent(in),optional :: trim_str !! if `val` is a string, then trim it.

    integer :: istat !! write `iostat` flag
    character(len=:),allocatable :: ifmt !! actual format string to use for integers
    character(len=:),allocatable :: rfmt !! actual format string to use for reals
    logical :: trimstr !! if the strings are to be trimmed
    character(len=max_real_str_len) :: real_val  !! for writing a real value
    character(len=max_integer_str_len) :: int_val !! for writing an integer value

    ! make sure the row isn't already finished
    if (me%icol<me%n_cols) then

        me%icol = me%icol + 1

        if (me%enclose_all_in_quotes) then
            write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%quote
        end if

        select type (val)
        type is (integer(ip))
            if (present(int_fmt)) then
                ifmt = trim(adjustl(int_fmt))
            else
                ifmt = default_int_fmt
            end if
            write(int_val,fmt=ifmt,iostat=istat) val
            write(me%iunit,fmt='(A)',advance='NO',iostat=istat) trim(adjustl(int_val))
        type is (real(sp))
            if (present(real_fmt)) then
                rfmt = trim(adjustl(real_fmt))
            else
                rfmt = default_real_fmt
            end if
            write(real_val,fmt=rfmt,iostat=istat) val
            write(me%iunit,fmt='(A)',advance='NO',iostat=istat) trim(adjustl(real_val))
        type is (real(wp))
            if (present(real_fmt)) then
                rfmt = trim(adjustl(real_fmt))
            else
                rfmt = default_real_fmt
            end if
            write(real_val,fmt=rfmt,iostat=istat) val
            write(me%iunit,fmt='(A)',advance='NO',iostat=istat) trim(adjustl(real_val))
        type is (logical)
            if (val) then
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%logical_true_string
            else
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%logical_false_string
            end if
        type is (character(len=*))
            if (me%enclose_strings_in_quotes .and. .not. me%enclose_all_in_quotes) &
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%quote
            if (present(trim_str)) then
                trimstr = trim_str
            else
                trimstr = .false.
            end if
            if (trimstr) then
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) trim(val)
            else
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) val
            end if
            if (me%enclose_strings_in_quotes .and. .not. me%enclose_all_in_quotes) &
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%quote
        type is (csv_string)
            if (me%enclose_strings_in_quotes .and. .not. me%enclose_all_in_quotes) &
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%quote
            if (present(trim_str)) then
                trimstr = trim_str
            else
                trimstr = .false.
            end if
            if (trimstr) then
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) trim(val%str)
            else
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) val%str
            end if
            if (me%enclose_strings_in_quotes .and. .not. me%enclose_all_in_quotes) &
                write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%quote
        class default
            if (me%verbose) write(error_unit,'(A)') &
                    'Error: cannot write unknown variable type to CSV file.'
        end select

        if (me%enclose_all_in_quotes) then
            write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%quote
        end if
        if (me%icol<me%n_cols) write(me%iunit,fmt='(A)',advance='NO',iostat=istat) me%delimiter

    else
        if (me%verbose) write(error_unit,'(A)') &
                'Error: cannot write more cells to the current row.'
    end if

    end subroutine add_cell